Disclosure: Prof Rozenberg has received research grants from Human Genome Sciences. Prof Bain is a clinical investigator and consultant for Human Genome Sciences. Prof McHutchison has received research grants in an advisory capacity from Human Genome Sciences, Schering Plough, and Roche. Prof Pulkstenis and Prof Subramanian are employed by Human Genome Sciences. Prof Neumann is a consultant for and has received research grants from Human Genome Sciences and Roche. He is a member of the speakers’ bureaus for Human Genome Sciences, Roche, and Schering Plough.